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PubMed2003

Identification of HIV type 2 subtype B transmission in East Asia.

We isolated an HIV-2 strain (01JP-IMCJ/KR020) from a Korean patient who has lived in Japan for the past 6 years. He was infected with HIV-2 through heterosexual contacts in either Korea or Japan. The phylogenetic analyses based on the near full-length nucleotide sequence revealed that 01JP-IMCJ/KR020 belongs to HIV-2 subtype B cluster with high bootstrap support. This isolate harbors a 13-nucleotide insertion upstream of the NF-KB site, which is one of the sequence signatures specific to HIV-2 subtype B. This represents the first report of HIV-2 subtype B transmission in East Asia; three cases of HIV-2 subtype A infection have been reported in Korea in 1991-1998. This suggests that at least sporadic transmission of HIV-2, including both subtypes A and B, occurs in East Asia. It is necessary to keep monitoring HIV-2 to see whether there is an increasing trend toward HIV-2 infection in this particular area in Asia.

Adult↗
PubMed2004

Cysticercosis/taeniasis in Asia and the Pacific.

Three taeniid tapeworms infect humans in Asia and the Pacific: Taenia solim, Taenia saginata, and Taenia asiatica. Although there is continuing debate about the definition of a new species, phylogenetic analyses of these parasites have provided multiple lines of evidence that T. asiatica is an independent species and the sister species of T. saginata. Here we review briefly the morphology, pathology, molecular biology, distribution and control options of taeniasis/cysticercosis in Asia and the Pacific and comment on the potential role which dogs may play in the transmission of T. solium. Special attention is focused on Indonesia: taeniasis caused by T. asiatica in North Sumatra, taeniasis/cysticercosis of T. solium and taeniasis of T. saginata in Bali, and taeniasis/cysticercosis of T. solium in Papua (formerly Irian Jaya). Issues relating to the spread of taeniasis/cysticercosis caused by T. solium in Papua New Guinea are highlighted, since serological evidence suggests that cysticercosis occurs among the local residents. The use of modern techniques for detection of taeniasis in humans and cysticercosis in humans, pigs and dogs, with the possible adoption of new control measures will provide a better understanding of the epidemiology of taeniasis/cysticercosis in Asia and the Pacific and lead to improved control of zoonotic and simultaneously meat-borne disease transmission.

Animals↗
PubMed2003

ECT in the Asia Pacific region: what do we know?

OBJECTIVE: To review and describe the practice of ECT in the Asia Pacific region in the year 2000. METHOD: A survey of 34 defined countries within the Asia Pacific region was made prior to the 1st Asia Pacific ECT Conference held in Melbourne, Australia, 2001. RESULTS: Contact addresses for 23 of 34 countries (70%) were found with responses from 12 different countries (35%). Individual responses were received from less than 1% of the total mail out for the conference. The percentage of inpatients who received ECT was consistently less than or equal to 9%, except for Nepal where it was 25.6%. Except for Kiribati and the Solomon Islands, all devices delivered brief pulse, square wave currents. All of the 12 countries surveyed used anesthesia, preferred bilateral electrode placement and reported a response rate of at least 86%. Adverse events were uncommon, memory being the most commonly reported side effect. Community attitudes were generally negative. CONCLUSION: Despite the difficulties in attempting to generalize about this huge and diverse region, a number of seemingly universal findings appeared in accord with the world literature. These included the widespread use of ECT, its effectiveness and its relative safety despite equally widespread community reluctance.

Asia↗
PubMed2002

A molecular phylogeny of ichthyophiid caecilians (Amphibia: Gymnophiona: Ichthyophiidae): out of India or out of South East Asia?

Recent molecular phylogenetic studies indicate that the rafting Indian plate harboured several isolated vertebrate lineages between ca. 130 and 56 Myr ago that dispersed and diversified 'out of India' following accretion with Eurasia. A single family of the amphibian order Gymnophiona, the Ichthyophiidae, presently occurs on the Indian plate and across much of South East Asia. Ichthyophiid phylogeny is investigated in order to test competing out of India and out of South East Asia hypotheses for their distribution. Partial sequences of mitochondrial 12S and 16S rRNA and cytochrome b genes for 20 ichthyophiids and proximate outgroups were assembled. Parsimony, maximum-likelihood and distance analyses all recover optimum trees in which uraeotyphlids plus Ichthyophis cf. malabarensis are the sister taxa to all other Ichthyophis, among which the South East Asian taxa are monophyletic. Tree topology and branch lengths indicate that the Indian lineages are more basal and older, and thus are more consistent with the hypothesis that ichthyophiids dispersed from the Indian subcontinent into South East Asia. The estimated relationships also support monophyly of Sri Lankan Ichthyophis, and non-monophyly of striped and unstriped Ichthyophis species groups. Mitochondrial DNA sequences provide evidence that should assist current problematic areas of caecilian taxonomy.

Amphibians↗
PubMed1992

The role of western Asia in modern human origins.

Western Asia provides the best collection of human skeletal remains relevant to the two basic models for the emergence of modern humans, namely the 'rapid replacement' and the 'regional continuity' models. Regardless of the taxonomies of particular hominids, their chronology is of crucial importance. Thermoluminescence (TL) and electron spin resonance (ESR) dates demonstrate that the Acheulo-Yabrudian and Mousterian entities and their associated fossils (Zuttiyeh, Tabun, Skhul, Qafzeh, Kebara, Shanidar, Amud) span the late Middle and Upper Pleistocene period. These new dates initiated major chronological revisions and renewed discussion of the cultural-archaeological implications. One of the most important conclusions is that the Middle to Upper Palaeolithic transition (or Revolution) 45-40 ka ago has nothing to do with the appearance of anatomically early modern humans in western Asia, which occurred some 100 ka ago or more. The Levant, the coastal region of the eastern Mediterranean, was both a corridor for movement of humans and animals as well as a refugium during climatically harsh periods. The mixture of morphological characteristics among the available Middle Palaeolithic human fossils is interpreted as reflecting the presence of immigrant and local populations. Archaeologically observable behavioural changes are taken as hints to the pre-adaptations of the Middle to Upper Palaeolithic revolution. The archaeological record of western Asia can contribute significantly to explaining the Middle to Upper Palaeolithic revolution. This region was the core area where the 'Neolithic Revolution' took place. The shift to systematic cultivation and the domestication of animals occurred within a short time.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Costs and health effects of breast cancer interventions in epidemiologically different regions of Africa, North America, and Asia.

We estimated the costs and health effects of treating stage I, II, III, and IV breast cancer individually, of treating all stages, and of introducing an extensive cancer control program (treating all stages plus early stage diagnosis) in three epidemiologically different world regions--Africa, North America, and Asia. We developed a mathematical simulation model of breast cancer using the stage distribution and case fatality rates in the presence and absence of treatment as predictors of survival. Outcome measures were life-years adjusted for disability (DALYs), costs (in 2000 U.S. dollars) of treatment and follow-up, and cost-effectiveness ratios (CERs; in dollars per DALY averted). Sensitivity analyses were performed to determine the robustness of the results. Treating patients with stage I breast cancer resulted in 23.41, 12.25, and 19.25 DALYs averted per patient in Africa, North America, and Asia, respectively. The corresponding average CERs compared with no intervention were 78 U.S. dollars , 1,960 U.S. dollars, and 62 U.S. dollars per DALY averted. The number of DALYs averted per patient decreased with stage; the value was lowest for stage IV treatment (0.18-0.19), with average CERs of 4,986 U.S. dollars in Africa, 70,380 U.S. dollars in North America, and 3,510 U.S. dollars per DALY averted in Asia. An extensive breast cancer program resulted in 16.14, 12.91, and 12.58 DALYs averted per patient and average CERs of 75 U.S. dollars, 915 U.S. dollars, and 75 U.S. dollars per DALY averted. Outcomes were most sensitive to case fatality rates for untreated patients, but varying model assumptions did not change the conclusions. These findings suggest that treating stage I disease and introducing an extensive breast cancer program are the most cost-effective breast cancer interventions.

Africa↗
PubMed2005

Systematic review and meta-analysis: enhanced efficacy of proton-pump inhibitor therapy for peptic ulcer bleeding in Asia--a post hoc analysis from the Cochrane Collaboration.

BACKGROUND: Proton-pump inhibitors reduce re-bleeding rates after ulcer bleeding. However, there is significant heterogeneity among different randomized-controlled trials. AIM: To see whether proton-pump inhibitors for ulcer bleeding produced different clinical outcomes in different geographical locations. METHODS: This was a post hoc analysis of our Cochrane Collaboration systematic review and meta-analysis of proton-pump inhibitor therapy for ulcer bleeding. Sixteen randomized-controlled trials conducted in Europe and North America were pooled and re-analysed separately from seven conducted in Asia. We calculated pooled rates for 30-day all-cause mortality, re-bleeding and surgical intervention and derived odds ratios and numbers needed to treat with 95% confidence intervals. RESULTS: There was no significant heterogeneity for any outcome. Reduced all-cause mortality was seen in the Asian randomized-controlled trials (odds ratios = 0.35; 95% confidence interval: 0.16-0.74; number needed to treat = 33), but not in the others (odds ratios = 1.36; 95% confidence interval: 0.94-1.96; number needed to treat--incalculable). There were significant reductions in re-bleeding and surgery in both sets of randomized-controlled trials, but the effects were quantitatively greater in Asia. CONCLUSIONS: Proton-pump inhibitor therapy for ulcer bleeding has been more efficacious in Asia than elsewhere. This may be because of an enhanced pharmacodynamic effect of proton-pump inhibitors in Asian patients.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Genetic structure of the whitefly Bemisia tabaci in the Asia-Pacific region revealed using microsatellite markers.

Bemisia tabaci (Hemiptera: Aleyrodidae) is a haplo-diploid species of sap-feeding insect belonging to the group of insects commonly known as whiteflies. From earlier analyses of mitochondrial and ribosomal markers it has been concluded that in the Asia-Pacific region there were three major indigenous races as well as a large collection of genotypes with no clear association with any race. This new study uses 15 microsatellite loci and demonstrates that the indigenous Asia-Pacific genotypes can be split into six genetic populations with little or no gene flow between them. These bare only superficial similarity to the mitochondrial and ribosomal defined races. Moreover, four of the six can be further split into two subpopulations that again show little evidence gene flow between them. While the patterns reflect a strong geographical structure, physical barriers alone cannot explain all the observed structure. Differential host-plant utilization explained some of the substructure, but could not explain the overall structure. The roles of mating interference and Wolbachia in developing the genetic structure are considered. The lack of gene flow between genetic populations and some subpopulations further suggests that the barriers were either sufficiently impermeable to immigration or that reproductive isolation and competitive interactions were sufficiently strong to prevent gene flow. If the latter is the case, it suggests that there may be as many as 10 morphologically indistinguishable species indigenous to the Asia-Pacific region.

Animals↗
PubMed2006

Three times out of Asia Minor: the phylogeography of Arabis alpina L. (Brassicaceae).

Arabis alpina is a characteristic plant in arctic-alpine habitats and serves as a classical example to demonstrate biology, ecology and biogeography of arctic-alpine disjuncts. It has a wider distribution than most other arctic-alpine plants, covering all European mountain systems, the Canary Islands, North Africa, the high mountains of East Africa and Ethiopia, the Arabian Peninsula and mountain ranges of Central Asia in Iran and Iraq. Additionally it is found in the northern amphi-Atlantic area including northeastern North America, Greenland, Iceland, Svalbard and northwestern Europe. We used markers from the nuclear (internal transcribed spacer of ribosomal DNA) and chloroplast genome (trnL-F region) to reconstruct its phylogeographic history. Both markers revealed clear phylogeographic structure. We suggest that A. alpina originated in Asia Minor less than 2 million years ago based on synonymous mutation rates of different genes (plastidic matK, nuclear adh and chs). From the Asian ancestral stock one group migrated via the Arabian Peninsula to the East African high mountains. A second group gave rise to all European and northern populations, and also served as source for the northwest African populations. A third group, which is still centred in Asia, migrated independently southwards and came into secondary contact with the East African lineage in Ethiopia, resulting in high genetic diversity in this area. In the Mediterranean regions, the genetic diversity was relatively high with numerous unique haplotypes, but almost without geographic structure. In contrast, the populations in the northern amphi-Atlantic area were extremely depauperate, suggesting very recent (postglacial) expansion into this vast area from the south.

Africa↗
PubMed2004

Report of the Asia-Pacific consensus on the management of gastroesophageal reflux disease.

This report summarizes the conclusions and recommendations of a panel of gastroenterologists practising in the Asia-Pacific region. The group recognized that although gastroesophageal reflux disease (GERD) is less common and milder in endoscopic severity in Asia than in the West, there is nevertheless data to suggest an increasing frequency of the disease. During a 2-day workshop, the evidence for key issues in the diagnosis and clinical strategies for the management of the disease was evaluated, following which the recommendations were made and debated. The consensus report was presented at the Asia-Pacific Digestive Week 2003 in Singapore for ratification. Upper gastrointestinal (GI) endoscopy is the gold standard for the diagnosis of erosive GERD. There is no gold standard for the diagnosis of non-erosive GERD (NERD). Diagnosis therefore relies on symptoms, a positive 24-h pH study or a response to a course of proton pump inhibitor (PPI) treatment. The goals of treatment for GERD are to heal esophagitis, relieve symptoms, maintain the patient free of symptoms, improve quality of life and prevent complications. The PPI are the most effective medical treatment. Following initial treatment, on-demand therapy may be effective in some patients with NERD or mild (GI) erosive esophagitis. Anti-reflux surgery by a competent surgeon could achieve a similar outcome, although there is an operative mortality of 0.1-0.8%. The decision is dependent on the patient's preference and the availability of surgical expertise. Currently, endoscopic treatment should be performed only in the context of a clinical trial. Treatment of patients with typical GERD symptoms without alarm features in primary care could begin with PPI for 2 weeks followed by a further 4 weeks before going to on-demand therapy.

Asia↗
PubMed2004

Survey on chronic pancreatitis in the Asia-Pacific region.

BACKGROUND AND AIMS: A survey was conducted of chronic pancreatitis (CP) in different countries in the Asia-Pacific region. The main objective of the survey was to generate a database containing information regarding the prevalence, etiology, clinical presentation, diagnostic work-up, and management of CP in the Asia-Pacific region. METHODS: Data were collected from seven countries using a structured questionnaire. Expert participants were asked to respond to the questionnaire based on the data of patients with CP studied in their centers. RESULTS: The prevalence of CP was found to be very high in southern India (114-200/100 000 population), in contrast to the low reported rate of 4.2/100 000 population in Japan. Alcohol was the most common etiological factor in Australia (95%) and Japan (54%) while idiopathic pancreatitis was the most common type in India (tropical pancreatitis) and China, accounting for approximately 70% of all cases of CP. Pain was the most common clinical feature. Diabetes and steatorrhea were uncommon. With regard to the diagnosis of CP, all the experts believed that a patient could be diagnosed as having CP in the presence of any one or more of the following: ductal changes on endoscopic retrograde cholangiopancreatography, a positive secretin test, pancreatic calcification, and endosonographic abnormalities suggestive of CP. Most experts suggested pancreatic enzymes and analgesics as initial medical therapy for pain relief in CP. Endotherapy was suggested as the therapy of choice if medical therapy failed. Surgery was offered only after the failure of endotherapy. Most experts agreed that research should focus on genetic abnormalities in CP and the role of endotherapy for pain relief. CONCLUSION: The survey brought out the prevalent types and presentation of CP, common management practices, and also the shortcomings in the existing knowledge of CP in the Asia-Pacific region. These findings might help focus attention on the research priorities for CP in this region.

Asia↗
PubMed2004

Clinical practice pattern of gastroenterologists, primary care physicians, and otolaryngologists for the management of GERD in the Asia-Pacific region: the FAST survey.

BACKGROUND AND AIM: The clinical practice patterns of gastroenterologists, primary care physicians, and otolaryngologists for the management of gastroesophageal reflux disease (GERD) in the Asia-Pacific region are unknown. Respective medical professionals from seven countries of the Asia-Pacific region were invited to participate in a questionnaire survey. METHODS: Five hundred and eighty-five medical professionals (221 gastroenterologists, 205 primary care physicians, and 159 otolaryngologists) participated in the survey. Three different versions of the questionnaire were used for each medical specialty. The questionnaire inquired about the prevalence, diagnosis, and management strategy of GERD for the respective medical professionals. RESULTS: All three medical specialties agreed that GERD is increasing and the most common diagnostic strategy used for patients with mild symptoms of GERD was 'treat before testing'. Gastroenterologists preferred 'test before treating' for patients with severe symptoms, but primary care physicians and otolaryngologists preferred 'treat before testing' for severe cases. Most medical professionals had heard of the proton pump inhibitor (PPI) empiric trial but only 33-52% of them had used it before. For mild and severe cases of GERD, gastroenterologists preferred the use of PPIs, while primary care physicians and otolaryngologists reserved PPIs for severe cases of GERD. Gastroenterologists preferred 'step down' approach, while the other two specialties preferred 'step-up' approach for the management of GERD. The preferred maintenance strategy for GERD was daily maintenance therapy among the three medical specialties. CONCLUSION: A clear evidence-based management strategy for the management of GERD is warranted in the Asia-Pacific region.

Anti-Ulcer Agents↗
PubMed2005

Chronic hepatitis B virus infection in the Asia-Pacific region and Africa: review of disease progression.

Countries in the the Asia-Pacific region and Africa tend to have the highest prevalence of hepatitis B infection worldwide. Hepatitis B infection progresses from an asymptomatic persistently infected status to chronic hepatitis B, cirrhosis, decompensated liver disease and/or hepatocellular carcinoma. The aim of this review was to summarize rates and risk factors for progression between disease states in the Asia-Pacific region and Africa. A literature search was conducted employing MEDLINE and EMBASE (1975-2003) using the following key words: hepatitis B, natural history, disease progression, cirrhosis, hepatocellular carcinoma, mortality, Africa and the Asia-Pacific region. Bibliographies of articles reviewed were also searched. Ranges for annual progression rates were: (i) asymptomatic persistent infection to chronic hepatitis B, 0.84-2.7%; (ii) chronic hepatitis B to cirrhosis, 1.0-2.4%; and (iii) cirrhosis to hepatocellular carcinoma, 3.0-6.6%. Patients with asymptomatic persistent infection and chronic hepatitis B had relatively low 5-year mortality rates (<4%); rates (>50%) were much higher in patients with decompensated liver disease and hepatocellular carcinoma. No data were found for progression rates in African populations. Hepatitis B e antigen was a risk factor for chronic hepatitis B, and bridging hepatic necrosis in chronic hepatitis B increased the risk of cirrhosis. Risk factors for hepatocellular carcinoma included cirrhosis, co-infection with hepatitis C virus, and genetic and environmental factors. In this review, wide ranges of disease progression estimates are documented, emphasizing the need for further studies, particularly in Africa, where progression rates are largely not available. Summarizing information on factors associated with disease progression should assist in focusing efforts to arrest the disease process in those at most risk.

Africa↗
PubMed2004

Natural disaster and mental health in Asia.

The purpose of the present article was to review the literature on disaster mental health in relation to natural disasters such as earthquakes, volcanic eruptions, typhoons and cyclones throughout Asia. Articles reviewed show that disaster psychiatry in Asia is beginning to emerge from and leave behind the stigma attached to mental health. The emergence of the acceptance of disaster mental health throughout Asia can be attributed in part to the acceptance of the notion of post-traumatic stress disorder (PTSD). This has allowed greater involvement of mental health professionals in providing ongoing support to survivors of natural disasters as well as providing greater opportunities for further research. Also, articles reviewed in the present paper commonly suggested the need for using standardized diagnostic tools for PTSD to appropriately interpret the discrepancy of results among studies. The importance of post-disaster support services and cultural differences is highlighted.

Asia↗
PubMed2001

Cardiovascular risk in the Asia-Pacific region from a nutrition and metabolic point of view: visceral obesity.

The association between abdominal obesity and an increased risk of cardiovascular disease (CVD) is now well recognized. Both problems are becoming more prevalent within the Asia-Pacific region, but there are substantial differences within and between countries. The strength of the temporal relationship between obesity and CVD in the region has led to the suggestion that obesity is the driving force behind the continuing epidemic of CVD. This raises the question as to whether there are any special aspects to the Asia-Pacific epidemic of obesity and resultant problems as a result of genetic or developmental factors. It is clear that the experience of central obesity and its cardiovascular consequences in western society cannot be directly transposed to all countries in the region. Issues such as smoking, alcohol use and inactivity may carry different implications. The Asia-Pacific region has started from low baseline prevalence of both obesity and CVD. but this implies that the potential for major problems in the future is particularly severe.

Adipose Tissue↗
PubMed2003

Molecular, serological, and virulence characteristics of Vibrio parahaemolyticus isolated from environmental, food, and clinical sources in North America and Asia.

Potential virulence attributes, serotypes, and ribotypes were determined for 178 pathogenic Vibrio parahaemolyticus isolates from clinical, environmental, and food sources on the Pacific, Atlantic, and Gulf Coasts of the United States and from clinical sources in Asia. The food and environmental isolates were generally from oysters, and they were defined as being pathogenic by using DNA probes to detect the presence of the thermostable direct hemolysin (tdh) gene. The clinical isolates from the United States were generally associated with oyster consumption, and most were obtained from outbreaks in Washington, Texas, and New York. Multiplex PCR was used to confirm the species identification and the presence of tdh and to test for the tdh-related hemolysin trh. Most of the environmental, food, and clinical isolates from the United States were positive for tdh, trh, and urease production. Outbreak-associated isolates from Texas, New York, and Asia were predominantly serotype O3:K6 and possessed only tdh. A total of 27 serotypes and 28 ribogroups were identified among the isolates, but the patterns of strain distribution differed between the serotypes and ribogroups. All but one of the O3:K6 isolates from Texas were in a different ribogroup from the O3:K6 isolates from New York or Asia. The O3:K6 serotype was not detected in any of the environmental and food isolates from the United States, and none of the food or environmental isolates belonged to any of the three ribogroups that contained all of the O3:K6 and related clinical isolates. The combination of serotyping and ribotyping showed that the Pacific Coast V. parahaemolyticus population appeared to be distinct from that of either the Atlantic Coast or Gulf Coast. The fact that certain serotypes and ribotypes contained both clinical and environmental isolates while many others contained only environmental isolates implies that certain serotypes or ribotypes are more relevant for human disease.

Animals↗
PubMed1994

Epidemiological study of Norwalk virus infections in Japan and Southeast Asia by enzyme-linked immunosorbent assays with Norwalk virus capsid protein produced by the baculovirus expression system.

In this study, we investigated Norwalk virus (NV) antigen and antibody to recombinant NV (rNV) in human populations in Japan and Southeast Asia by enzyme-linked immunosorbent assays (ELISAs). Baculovirus-expressed recombinant NV (rNV) capsid protein was used for preparing antisera to rNV or used as an antigen for detecting antibody to rNV. The ELISAs were specific for NV and had sensitivities equivalent to or higher than those of the previously developed radioimmunoassays. In 159 stool samples obtained from children, mainly younger than 10 years old, with acute gastroenteritis due to small round structured viruses in Japan, only 1 was positive for NV antigen. The pattern of acquisition of antibody to rNV was quite different from those of antibodies to group A rotavirus and human calicivirus Sapporo (HuCV-Sa) strain. The prevalence of antibody to rNV remained at a low level throughout childhood and then showed a steep rise during school age and early adulthood in Japan. A high prevalence of antibody was observed in samples collected from healthy adults in Japan and Southeast Asia. These results suggested that NV infection is common in adults in Japan and Southeast Asia but may be rare in infants in Japan. The HuCV-Sa strain was negative by the ELISA, and no serological relationship between NV and the HuCV-Sa strain was found. NV may be quite different from the HuCV-Sa strain, although both viruses are classified in the family Caliciviridae.

Adolescent↗
PubMed2003

Origin and evolution of Japanese encephalitis virus in southeast Asia.

Since it emerged in Japan in the 1870s, Japanese encephalitis has spread across Asia and has become the most important cause of epidemic encephalitis worldwide. Four genotypes of Japanese encephalitis virus (JEV) are presently recognized (representatives of genotypes I to III have been fully sequenced), but its origin is not known. We have determined the complete nucleotide and amino acid sequence of a genotype IV Indonesian isolate (JKT6468) which represents the oldest lineage, compared it with other fully sequenced genomes, and examined the geographical distribution of all known isolates. JKT6468 was the least similar, with nucleotide divergence ranging from 17.4 to 19.6% and amino acid divergence ranging from 4.7 to 6.5%. It included an unusual series of amino acids at the carboxy terminus of the core protein unlike that seen in other JEV strains. Three signature amino acids in the envelope protein (including E327 Leu-->Thr/Ser on the exposed lateral surface of the putative receptor binding domain) distinguished genotype IV strains from more recent genotypes. Analysis of all 290 JEV isolates for which sequence data are available showed that the Indonesia-Malaysia region has all genotypes of JEV circulating, whereas only more recent genotypes circulate in other areas (P < 0.0001). These results suggest that JEV originated from its ancestral virus in the Indonesia-Malaysia region and evolved there into the different genotypes which then spread across Asia. Our data, together with recent evidence on the origins of other emerging viruses, including dengue virus and Nipah virus, imply that tropical southeast Asia may be an important zone for emerging pathogens.

Amino Acid Sequence↗